Tweak logic for when to display:

schmiddy · schmiddy · commit 8f61e44efd34 · 2015-01-11T19:31:09.000-05:00
"Waiting for %d transactions to finish. First PID: %s"

message. Display it on every loop through the SQL_XID_ALIVE check
(i.e. every second), instead of only when the number of transactions
we're waiting on changes -- previously, it was too easy for that
important message to get lost in other messages.

And don't display the message at all when running under pg_regress,
i.e. as part of `make installcheck`. We had been getting occasional
errors from pg_regress when autovacuum was running and that message
got logged.
diff --git a/bin/pg_repack.c b/bin/pg_repack.c
@@ -987,7 +987,6 @@ repack_one_table(repack_table *table, const char *orderby)
 	PGresult	   *res = NULL;
 	const char	   *params[2];
 	int				num;
-	int				num_waiting = 0;
 	char		   *vxid = NULL;
 	char			buffer[12];
 	StringInfoData	sql;
@@ -997,6 +996,11 @@ repack_one_table(repack_table *table, const char *orderby)
 	char		    indexbuffer[12];
 	int             j;
 
+	/* appname will be "pg_repack" in normal use on 9.0+, or
+	 * "pg_regress" when run under `make installcheck`
+	 */
+	const char     *appname = getenv("PGAPPNAME");
+
 	/* Keep track of whether we have gotten through setup to install
 	 * the z_repack_trigger, log table, etc. ourselves. We don't want to
 	 * go through repack_cleanup() if we didn't actually set up the
@@ -1312,15 +1316,14 @@ repack_one_table(repack_table *table, const char *orderby)
 		if (num > 0)
 		{
 			/* Wait for old transactions.
-			 * Only display the message below when the number of
-			 * transactions we are waiting on changes (presumably,
-			 * num_waiting should only go down), so as not to
-			 * be too noisy.
+			 * Only display this message if we are NOT
+			 * running under pg_regress, so as not to cause
+			 * noise which would trip up pg_regress.
 			 */
-			if (num != num_waiting)
+
+			if (!appname || strcmp(appname, "pg_regress") != 0)
 			{
 				elog(NOTICE, "Waiting for %d transactions to finish. First PID: %s", num, PQgetvalue(res, 0, 0));
-				num_waiting = num;
 			}
 
 			CLEARPGRES(res);
